The deep drama, for lovers of Sudan, that surrounded Luis Moreno-Ocampo's request that President Omar al-Bashir be indicted for genocide, war crimes and crimes against humanity was briefly interrupted, quite unwittingly, by state television yesterday a few hours after Ocampo spoke. First, we had Vice President Ali Osman Mohamed Taha insisting that the catastrophe in Darfur has nothing to do with the president: it preceded his arrival in power 19 years ago. Then television cut to Bashir, who is accused by Ocampo, chief prosecutor of the International Criminal Court, of personally masterminding an "ongoing" campaign of genocide.

Ocampo's initiative, Bashir said, was irrelevant because Sudan does not recognise the ICC. Nothing new so far; this is a standard (and irrelevant) government line. But then the president broke new ground. The chief prosecutor had been invited to Sudan, he said, and had seen the reality of Darfur for himself. Soon after, television centre cut in with the national anthem and random pictures of Sudanese landscapes.

Far from being a criminal mastermind in full control of the state apparatus, as Ocampo alleges, Bashir looked like someone rather out of the flow of things. The president, of course, got his facts wrong: Ocampo has never been to Sudan, far less to Darfur. Some ICC staff have visited Khartoum, to determine whether the government was organising genuine trials of its own (which it isn't), but none of them has ever been permitted to set foot in Darfur.

Despite the tremendous difficulties that have faced the ICC in seeking to determine responsibility for the horrors of Darfur, Ocampo has not pulled his punches. Last year, the ICC indicted Janjaweed leader Ali Kushayb and Ahmed Haroun, minister of state for humanitarian affairs, for war crimes and crimes against humanity. Outside Sudan government circles, not a single voice was heard questioning the correctness of these charges. In the case of Bashir, however, Ocampo has added the third charge of genocide – which human rights groups gave avoided – and will now have to prove that Bashir personally had the "intent [the italics are mine] to destroy, in whole or in part, a national, ethnic, racial or religious group".

Or, in Ocampo's own words, that the counterinsurgency that followed the rebellion in Darfur in 2003 was an "alibi".

A number of eminent lawyers have already questioned the wisdom of Ocampo's decision to go for broke. William Schabas of the rights centre at the National University of Ireland – a strong supporter of indicting the president, and considered by some to be the leading expert on genocide law – has said the "wise course" would have been to charge crimes against humanity.

"Genocide is reserved for the physical extermination of ethnic groups, and I think most observers would agree that's not what we're seeing here," he is quoted as saying in the Guardian. "This looks like a bit of grandstanding, popular in some quarters – but, if the judges follow the law, they will acquit Bashir."

Others, including Antonio Cassese, first president of the International Criminal Tribunal for the Former Yugoslavia (ICTY) and a passionate supporter of the ICC, have asked why Ocampo chose to issue a public application, rather than a sealed warrant, if he was serious about prosecuting.

It was perhaps necessary to issue public applications for the first indictments last year, to give Khartoum the chance of cooperating with the ICC. But Haroun has neither been handed to the court nor stripped of his humanitarian portfolio. Rather, he has been given added responsibilities: on September 2 2007, he was nominated to the joint chairmanship of a fact-finding a committee on human rights violations and breaches of the transitional constitution in the south and north of Sudan; on November 18 2007, he was appointed to the force monitoring mechanism group of the Darfur peacekeeping force Unamid, established by Bashir himself.

If Bashir did not surrender Haroun, he is certainly not going to surrender himself. And arresting him is going to be difficult – not only because the ICC is not allowed in Sudan, but because Ocampo chose to reveal, in an interview barely a month ago, that he had plans to divert a plane carrying Haroun to the Haj in order to arrest him. The Sudan government learned of the plan, and Haroun cancelled his flight.

In the Pandora's box of uncertainties Ocampo has opened, one thing is beyond doubt: the president of Sudan is going to think twice before boarding any airliner now.

Ocampo has taken a maximalist position that he must now defend. First, to the pre-trial chamber of the ICC and the court of world opinion – most critically, in the Arab-Islamic world and on the African continent. Then, if Bashir is ever arrested, in a court of law. If Bashir is found guilty and convicted, it will be a victory for the ICC (if not necessarily for lasting peace and stability in Sudan).

But if he continues in power, and possibly is re-elected as president in elections next year, it will not only be a snub to the ICC. It will be an advertisment for impunity.